Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Y	Dec. 31, 2010	Dec. 31, 2009
Lease Commitments
Minimum term of non-cancelable lease commitments for further disclosure (in years)	1
Rental expense	$ 70.1	$ 72.4	$ 75.8
Operating lease payments due to various related parties	4.8	4.1	3.7
Operating Leases
2012	55.7
2013	45.5
2014	35.9
2015	26.1
2016	20.5
Thereafter	75.7
Total	259.4
Capital Leases
2012	0.7
2013	0.6
2014	0.6
2015	0.3
Total	2.2
Less interest	(0.1)
Capital lease obligations	2.1
Less current portion	(0.6)
Long-term capital lease obligations	$ 1.5

Represents the minimum term of non-cancelable lease commitments for further disclosure.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid within one year (or one operating cycle, if longer) of the balance sheet date.

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Amount necessary to reduce net minimum lease payments to present value calculated at the lesser of the interest rate implicit in the lease (if known) or the entity's incremental borrowing rate (as defined) at inception of the lease.

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The discounted value of future cash flows under leases meeting the criteria for capitalization.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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